Stereoregularity Improvement and Frontal Substituents

Temperature (°C) Miff (kDa) rrrr (%) rmmr (%) rrmr (%) Melting point (°C) 

The data clearly shows, as anticipated, a substantial decrease in rmmr pentad concentrations related to meso triad (nun) stereoerrors in the backtxuie of syndiotactic polymer chains produced with 9/MAO compared to the corresponding polymers produced with 1/MAO at comparable polymerizatiOTi temperatures. Interestingly, even the rmnr pentad concentrations in polymers produced with 9/MAO, directly proportional to the catalyst s site epimerizatiOTi frequency, are lower than the observed rmnr pentad concentration for polymers produced with 1 (and 6). For syndiotactic polymers produced with both catalyst systems, the rmnr pentad concentrations almost double with every 20 C increase in polymerization temperature with the same rate. On the other hand, the enantiomorphic site control related rmmr pentad concentrations in syndiotactic polymers produced at different temperatures 

2 Computational Calculations Determination and/or Prediction of Enantioselectivity of Syndiospecific 

From the above calculation and discussion, two conclusions can be drawn regarding the origin and factors impacting the enantioselectivity of the syndiospecific catalyst systems  

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